Articles can wear over time, such as due to frictional contact, chemical machining, or abrasion, for example. One such article is a substrate, such as may be part of a semiconductor and/or part of a micro-electro-mechanical system (MEMS). By way of example, during a semiconductor fabrication process a substrate can undergo multiple iterations of processing steps, which can include, for example, etching, stripping, chemical mechanical polishing (CMP), and/or washing. During these steps, some of the substrate and/or some or all of one or more layers of material applied to the substrate can be selectively removed. For example, during CMP, one or more polishing and/or buffing pads having a certain degree of abrasiveness can be urged against and moved (e.g., rotated) relative to a surface of the substrate to remove, polish back and/or planarize the surface of the substrate and/or one or more layers of material formed thereon.
Additionally, polishing and buffing pads can themselves wear during CMP processing. For instance, polishing and buffing pads can become thinner due to mechanical loss of material as they polish and buff. These pads have to be replaced when they become overly thin and worn.
MEMS devices can also experience surface wear and material loss during normal operation. For instance, under typical operating conditions, one or more portions of a MEMS device frequently come into some type of frictional contact (e.g., sliding, rotating or otherwise) with another member, such as from the same or another MEMS device or another article with which the MEMS device is cooperating. As a result, one or more areas of the MEMS device can experience surface wear. Repeated exposure to such mechanical interaction can lead to device failure, inoperability or malfunction.